1. Field of the Invention
This invention relates to air conditioning apparatus and, more particularly, to a terraced water distributor for an evaporative air conditioner.
2. State of the Art
Evaporative air conditioners generally include an anti-pervious outer housing with porous, air-pervious, wettable pads mounted against the inner surfaces of the housing. A liquid distribution system provides cooling water to the pads to maintain them in saturated condition. Hot, dry ambient air is drawn through the saturated pads by a suction fan which is located within the housing. As the hot, dry air comes into contact with the wettable pads, evaporative heat exchange occurs. That is, the ambient air passing through the pads becomes saturated with water vapor. This phenomenon results in cooling of the ambient air by converting the sensible heat of the ambient air to latent heat suspended in the vaporized moisture.
Typically, the water distribution systems of an evaporative air conditioner supplies water to the upper edges of the wettable pads. Water then flows downwardly through the pads to saturate them throughout. For example, U.S. Pat. No. 4,029,723 discloses a water distribution system wherein a V-shaped trough is positioned above the upper edges of the wettable pads. The trough has holes formed in it to allow water to trickle from the trough onto the pads. Water is supplied to the trough by a water distribution tube which is mounted on a ledge within the trough. The distribution tube also has holes in it for discharging water into the trough. Water is supplied to the distribution tube by a sump pump which is located in a liquid reservoir formed as part of the base of the air conditioner.
Another type of water distribution system is taught by U.S. Pat. No. 3,867,486. That patent discloses an evaporative air conditioner which utilizes a flat rectangular water distribution tray having a channel which extends around the periphery of the tray. The channel is located above the upper edges of the air conditioner's wettable pads and has holes formed in it for discharging water onto the pads. Formed in the tray are a number of water supply grooves which extend outwardly from a central feed cup to the peripheral channel. The central feed cup is connected by a hose to a sump pump located in a liquid reservoir. The reservoir is formed as a part of the base of air conditioner and supplies water to the feed cup. Water supplied to the peripheral channel drops through the holes in the channel onto the upper edges of the wettable pads to maintain the pads in a saturated condition.
Yet another type of distribution system is taught by U.S. Pat. No. 2,325,692. That patent discloses a cylindrical evaporative air conditioner which utilizes a conical water distributor. The outer edge of the distributor is positioned above the upper edge of the air conditioner's cylindrical wettable pad. A sump pump delivers water from a reservoir formed as part of the base of the air conditioner to a funnel-shaped, perforated outlet which is mounted at the apex of the surface of the distributor. Water flows downwardly by gravity from the perforated outlet to the edges of the distributor. Water then falls from the edge of the distributor onto the upper edge of the wettable pad.
A still further type of liquid distributor, disclosed in co-pending U.S. patent application Ser. No. 111,612, includes surfaces which slope downwardly from the center of the distributor toward the upper edges of the air conditioner housing. Radial grooves are formed in the surfaces of the distributor which slope toward the air-pervious portions of the housing. A pump supplies liquid to the distributor such that liquid flows by gravity through the radial grooves and directly onto the upper edges of the wettable pads.